Friday, April 23, 2010
Most of my posts are fairly light hearted, have little fun facts and humor. This one is very serious though. I was writing out a recipe for a friend and I mentioned that she must avoid a certain brand of cocoa due to the high concentrations of acrylamide and realized I really should write here about it.
Acrylamide occurs as odorless, white crystals. It is soluble in water and evaporates slowly at room temperature. As an industrial chemical, acrylamide is used in waste-water treatment, paper and pulp processing, mineral processing, and other industrial work. All acrylamide in the environment is man-made.
Acrylamide is readily absorbed by ingestion, inhalation, and absorption through the skin. It is a neurotoxin and is classified as a probable carcinogen to humans by the International Agency for Research on Cancer. The US National Institutes of Health also lists the substance as a probable human carcinogen and neurotoxin. Germany's Federal Institute for Risk Assessment additionally suggests the risk of DNA damage from acrylamide exposure.
Acrylamide is quite toxic. The US EPA's "safe" level for acrylamide—the concentration at which exposure presents a cancer risk to one in one million people— is set at a low value of 0.00077. Compare that to the much higher allowed safe levels for several better known toxins:
• Benzene – 0.12
• Carbon tetrachloride – 0.067
• Chloroform – 0.043
• Lead – 0.013
Researchers in Europe and the United States have found acrylamide in certain foods that were heated to a temperature 248 degrees Fahrenheit, but not in foods prepared below this temperature.
Potato chips and French fries were found to contain higher levels of acrylamide compared with other foods. The World Health Organization (WHO) and the Food and Agriculture Organization (FAO) stated that the levels of acrylamide in foods pose a “major concern” and that more research is needed to determine the risk of dietary acrylamide exposure.
There is still much scientific work to be done to determine the levels of acrylamide in specific foods. But a broad trend has emerged: Foods with high levels of carbohydrates that are cooked at high temperature appear to be the main sources of acrylamide in food.
The level of acrylamide in food can vary considerably, apparently due to the particular processing or cooking conditions used. The levels of acrylamide increase with the time span of heating. Acrylamide formation has not been observed at temperatures below 120 degrees C (248 degrees F).
The main offending food groups are below, listed roughly in descending order of acrylamide content:
• Potato Chips
• French Fries
• Crackers, Toast, Bread Crisps, Cookies
• Boxed Breakfast Cereal
• Corn Chips
• Bakery Products
Research is just beginning on how acrylamide forms in cooked food, but potato chips and french fries appear to be particularly susceptible to acrylamide formation because of their high levels of certain types of carbohydrates.
Bread actually contains fairly low levels of acrylamide compared to high-level sources like potato chips, but the large amount of bread consumed by the average person makes it a noteworthy source.
Coffee and cocoa are surprise sources of acrylamide. In fact, some studies have found coffee to be the highest source of dietary acrylamide for some people. The problem lies not in the brewing of the coffee but in the roasting of the beans. As with bread, the per-unit content of acrylamide in coffee or cocoa is not especially high, but the quantity of these foods that one consumes can raise the total acrylamide level ingested to troublesome levels.
Research it for yourself, and take a look at this site to check levels in certain brands of foods you may purchase, including baby food!